Sony Alpha A77 with 16-50mm lens review

The letters SLT in the name stand for single-lens translucent, which marks out the A77 as different from single-lens reflex cameras. Conventional SLRs have a mirror that directs light to the viewfinder and autofocus system, and flips out of the way to let light hit the sensor to capture a picture. The A77’s mirror is translucent, so light reaches the autofocus and imaging sensors simultaneously. We explored the pros and cons of this approach in our review of the Sony Alpha SLT-A33L, but to summarise, it means that phase-detect autofocus works at the same time as live view, burst shooting and video capture. The downside is that it reduces the amount of light hitting the sensor. The A77’s ISO speed values are calibrated to compensate, but it does push up noise levels compared to the same sensor in another type of camera.

It also means that the viewfinder is electronic rather than optical, but in the A77’s case it’s hard to see this as a drawback. This electronic viewfinder’s generous size and 2.4-megapixel resolution give a clearer view than any optical viewfinder we’ve used, and it’s useful that white balance and exposure settings are reflected in the image. One hitch with previous Sony SLT cameras was that this made shooting with manual exposure and our wireless flash rig impossible, as the live view image was virtually pitch black. Thankfully, the A77 includes an option for the live view image to ignore exposure settings.

Putting the button lag issue to one side, this is a quick camera, taking one second to power up and shoot, and just 0.4 seconds between shots, although this slowed to 1.5 seconds after six frames when shooting in raw mode.

Because the autofocus and imaging sensors work concurrently, the top 12fps burst mode comes with continuous autofocus – an astounding feat, although the much cheaper Sony Alpha SLT-A55 isn’t far behind at 10fps. Sadly, this performance only lasted for 13 shots before slowing to 0.8fps for JPEGs or 0.7fps for raw (we tested with a Panasonic UHS-1 SDHC card). This 12fps speed is available via a dedicated mode on the dial, which prohibits aperture and shutter speed control. However, unlike on the A55’s similar mode, there is still access to ISO speed. The screen and viewfinder show captured shots rather than a live view while capturing, so tracking fast-moving subjects was tricky.

Burst shooting in priority and manual exposure modes is either at 8fps or 3fps, but live view is only available at 3fps. Both modes only lasted for around a dozen shots before slowing down to around 1fps. That’s the downside of the huge 24-megapixel resolution; JPEGs weigh in at around 14MB, which is a lot of data to shift around.